Pharmacological ascorbate induces sustained mitochondrial dysfunction

Published by Elsevier Inc..

Pharmacological ascorbate (P-AscH-; high dose given intravenously) generates H2O2 that is selectively cytotoxic to cancer compared to normal cells. The RAS-RAF-ERK1/2 is a major signaling pathway in cancers carrying RAS mutations and is known to be activated by H2O2. Activated ERK1/2 also phosphorylates the GTPase dynamin-related protein (Drp1), which then stimulates mitochondrial fission. Although early generation of H2O2 leads to cytotoxicity of cancer cells, we hypothesized that sustained increases in H2O2 activate ERK-Drp1 signaling, leading to an adaptive response; inhibition of this pathway would enhance the toxicity of P-AscH-. Increases in phosphorylated ERK and Drp1 induced by P-AscH- were reversed with genetic and pharmacological inhibitors of ERK and Drp1, as well as in cells lacking functional mitochondria. P-AscH- increased Drp1 colocalization to mitochondria, decreased mitochondrial volume, increased disconnected components, and decreased mitochondrial length, suggesting an increase in mitochondrial fission 48 h after treatment with P-AscH-. P-AscH- decreased clonogenic survival; this was enhanced by genetic and pharmacological inhibition of both ERK and Drp1. In murine tumor xenografts, the combination of P-AscH- and pharmacological inhibition of Drp1 increased overall survival. These results suggest that P-AscH- induces sustained changes in mitochondria, through activation of the ERK/Drp1 signaling pathway, an adaptive response. Inhibition of this pathway enhanced the toxicity P-AscH- to cancer cells.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:204

Enthalten in:

Free radical biology & medicine - 204(2023) vom: 01. Aug., Seite 108-117

Sprache:

Englisch

Beteiligte Personen:

Carroll, Rory S [VerfasserIn]
Du, Juan [VerfasserIn]
O'Leary, Brianne R [VerfasserIn]
Steers, Garett [VerfasserIn]
Goswami, Prabhat C [VerfasserIn]
Buettner, Garry R [VerfasserIn]
Cullen, Joseph J [VerfasserIn]

Links:

Volltext

Themen:

Antineoplastic Agents
Ascorbic Acid
BBX060AN9V
DNM1L protein, human
EC 2.7.11.24
EC 3.6.5.5
Extracellular Signal-Regulated MAP Kinases
Hydrogen Peroxide
Journal Article
Mitochondrial dynamics
Mitochondrial fission
Oxidative stress
PQ6CK8PD0R
Pharmacological ascorbate
Reactive Oxygen Species
Research Support, N.I.H., Extramural

Anmerkungen:

Date Completed 22.11.2023

Date Revised 06.12.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.freeradbiomed.2023.04.023

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM356406369